There exist, at least on paper, rotary volumetric machines of the type comprising a stator in which a chamber of suitable shape is provided, a rotor secured to a shaft being disposed in said chamber whilst the movable elements of the blade type ensure variations of volume, these machines can be roughly divided into the following families:                a family of machines in which the blades move radially in the rotor, which is represented among other documents by the patents FR-A-2806751, FR-A-2792364, WO-A-0109485, WO-A-0057027, WO-A-0052306, WO-A-0023692, EP-A-1043504, EP-A-1001172, EP-A-1118773, FR-A-2807792, EP-A-1043503, EP-A-1035327, EP-A-1008753, WO-A-9911907, WO-A-0055478, GB-A-744247, EP-A-1055823, WO-A-0075517 and DE-A-19815093;generally speaking, the machines of this family have it in common:        that they have more than one blade per rotor, which limits the ratio between the greatest and the least volume comprised between the blades,        that the movable elements are subject to centrifugal force generated by the rotation of the rotor and are applied with more or less force against the interior wall of the stator, which gives rise to more or less great friction and contact pressure,        that said friction must be lubricated, which does not permit this type of machine to operate dry, nor at high temperatures;        a family of machines in which the blades are articulated in the rotor, which is represented among other documents by the patents WO-A-9961752, WO-A-9857039, WO-A-0111196, WO-A-0120132 and U.S. Pat. No. 4,451,215;generally speaking, the machines of this family have in common:        that they have more than one blade per rotor, which limits the ratio between the greatest and least volume comprised between the blades,        that the movable elements are subject to centrifugal force generated by rotation of the rotor, even if mechanical devices which are either of one piece with the rotor, or bodies with the rotor limiting the friction pressure, the clearance due to tolerances of machining or wear giving rise sooner or later to greater or lesser friction and contact pressures,        that said friction must be lubricated, which does not permit this type of machine to run dry, nor at high temperatures;        a family of machines in which the blades are articulated in the rotor and in the stator, which is represented among other documents by the patents U.S. Pat. Nos. 1,253,460, 1,886,206 and WO-A-0075517;        generally speaking, the machines of this family have it in common:        that they have more than one blade per rotor, which limits the ratio between the least and greatest volume comprised between the blades,        that the articulations are disclosed in the working volume, that there must be lubricated and that because of this, the machines cannot run dry nor at high temperatures;        a family of machines in which the blades are articulated in the stator, which is represented among other documents by the patents U.S. Pat. No. 4,772,185 and EP-A-0120993;generally speaking, the machines of this family have it in common:        that they have more than one blade per rotor, which limits the ratio between the least and greatest volume comprised between the blades,        that the articulations are disposed in the working volume, which must be lubricated and accordingly these machines cannot run dry nor at high temperatures;        that the blades are maintained applied against the rotor with the help of springs, which does not permit using these machines at high temperatures;        a family of machines in which the blades are articulated in the rotor, whilst elements of the abutment type form a body with the stator, which is represented among other documents by the patent WO 01/46561; generally speaking, the machines of this family have it in common:        that they have more than one blade per rotor, which limits the ratio between the greatest and least volume comprised between the blades;        that the movable elements are subject to centrifugal force generated by rotation of the rotor and are applied with more or less force against the internal wall of the stator, which gives rise to more or less great contact pressures and friction;        that the articulations are disposed in the working volume and that because these articulations must be lubricated, these machines cannot run dry nor at high temperatures;        that the blades, according to the speed of rotation, enter into more or less violent contact with said abutments, which can give rise not only to undesirable noise, but above all the rapid degradation of the portions that must assure sealing;        a family of machines in which the elements of the blade type are of one piece with the rotor whilst the elements in the nature of abutments are articulated in the rotor, which is represented among other documents by the patent WO 00/73627;generally speaking, the machines of this family have it in common:        that they have more than one blade per rotor, which limits the ratio between the greatest and least volume comprised between the blades;        that the abutments are maintained applied against the rotor with the help of springs, which does not permit using these machines at high temperatures;        that the articulations are disposed in the working volume and that because of this, said articulations must be lubricated, so that these machines cannot run dry nor at high temperatures;        that the blades, according to the speed of rotation, enter into more or less violent contact with said abutments, which can give rise not only to undesirable noise but above all the rapid degradation of the parts that must ensure sealing.        
Finally, there is known from GB 2254888 a pump or motor with a rotatable piston in which a flap can be moved between a retracted position and an extended position in the working cylinder. The flap comes into contact against a rotor element to produce the separation into two zones of the volume of the working cylinder. As the flap wears, the contact surfaces must be lubricated, which does not permit this machine to operate dry at high temperatures.
Generally speaking, the machine according to the present application, permits overcoming one or several of the mentioned drawbacks.